Which of the following is a correct way to define an object using an object literal?
A). var car = {make: 'Toyota', model: 'Corolla'};
B). var car = make: 'Toyota', model: 'Corolla';
C). var car = new Object(make: 'Toyota', model: 'Corolla');
D). var car = Object.create(make: 'Toyota', model: 'Corolla');
How can you iterate over all properties of an object?
A). for (var key of object)
B). for (var key in object)
C). for (var key with object)
D). for (var key over object)
How do you define a constructor function for a Car object?
A). function Car(make, model, year) { this.make = make; this.model = model; this.year = year; }
B). Car(make, model, year) { this.make = make; this.model = model; this.year = year; }
C). function create Car(make, model, year) { this.make = make; this.model = model; this.year = year; }
D). function construct Car(make, model, year) { this.make = make; this.model = model; this.year = year; }
How do you create a method inside an object using an object literal?
A). methodName: function() {}
B). methodName = function() {}
C). methodName: () {}
D). methodName: method() {}
How do you define a class in JavaScript ES6?
A). class ClassName { constructor() {} }
B). function ClassName() { constructor() {} }
C). class ClassName() { constructor {} }
D). function class ClassName { constructor() {} }
What does Object.assign(target, ...sources) do?
A). Copies properties from sources to target
B). Compares properties between target and sources
C). Deletes properties in sources
D). Merges properties of sources into target and removes duplicates
What is encapsulation in the context of JavaScript objects?
A). Hiding the internal state and requiring all interaction to be performed through an object's methods
B). Extending one object from another
C). Creating a new object
D). Removing a property from an object
What will car['make'] return if var car = {make: 'Ford', model: 'Mustang'};?
A). Ford
B). Mustang
C). Undefined
D). Error
What is the purpose of the this keyword in an object method?
A). It refers to the global object.
B). It refers to the current object.
C). It refers to the parent object.
D). It refers to the previous object.
How can you check if a property exists in an object?
A). 'property' in object
B). object.hasProperty('property')
C). object.contains('property')
D). object.includes('property')